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K Otto

Publications and source records attributed to K Otto.

18 recordsLinked to original sources
PubMed1992

Ageing and changes in protein conformation in the human lens: a Raman microspectroscopic study.

Using confocal Raman microspectroscopy with laser light of 660 nm the secondary and tertiary conformation of crystallins was studied in human lenses of varying age (20-75 years). Differences in cortical and nuclear proteins in individual lenses and among lenses of different age and differences between small equatorial opacities and adjacent clear sites were analysed using a difference spectrum approach. Intensity calibration allows assessment of local variations in protein content. The main findings and conclusions are as follows. (1) Irrespective of the age of the lens nuclear proteins proved to contain more aromatic amino acids, i.e. tryptophan, tyrosine and phenylalanine. This change most probably reflects differences in crystallin composition between nucleus and cortex as described in biochemical studies. (2) Changes in the amide bands indicate a more pronounced beta-sheet conformation of the nuclear proteins. Taking into account available biochemical evidence this most probably reflects a true post-translational change in the secondary conformation of the crystallins. (3) Cortical proteins in 'old' and 'young' lenses are largely identical indicating that ageing is not accompanied by gross alterations in the transcription/translation of the crystallin genes. (4) 'Old' and 'young' nuclear proteins deviate with respect to the amount of aromatic amino acids, being more abundant in 'young' nuclear proteins. (5) Proteins in small early opacities do not exhibit alterations in conformation. (6) A pronounced peak in the difference spectra in the region 1425-1435 cm-1 for nuclear proteins especially when compared with equatorial cortical proteins may be considered as evidence for the advanced photooxidation of tryptophan and/or deamidation of asparagine from superficial to deep regions of the lens.

Adult↗
PubMed1992

[Malignant hyperthermia as a complication of anesthesia in the dog].

A moderate malignant hyperthermia developed in a Labrador Retriever anaesthetized with isoflurane for a femoral shaft fracture repair. Signs of malignant hyperthermia included progressive increases in PETCO2 and rectal temperature up to 39.8 degrees C, tachycardia, cyanosis, and elevated serum levels of potassium, inorganic phosphorus, AST, CK and alkaline phosphatase. Treatment initiated in the early recovery period consisted of hyperventilation with 100% oxygen, stomach lavage with iced water, body surface cooling, and intravenous administration of cold isotonic saline solution. Cooling was continued until the rectal temperature had dropped to 37.3 degrees C. After treatment the dog recovered uneventfully. Clinical signs, pathophysiology, therapy, prevention of malignant hyperthermia and its association with other disorders are discussed.

Anesthesia↗
PubMed1992

Comparison of neurologic responses to the use of medetomidine as a sole agent or preanesthetic in laboratory beagles.

Different dose regimens of medetomidine (a potent alpha 2-adrenergic agonist), adding up to a combined dose of 80 micrograms/kg, were administered to laboratory beagles to determine physiologic responses including neurologic. The study was intended to determine EEG responses where sufficient sedative and analgesic effects are reached with medetomidine and in contrast its effects when used with ketamine or halothane. Cardiopulmonary responses were very similar in each dose regimen, showing the characteristic properties of single doses of 80 micrograms/kg of medetomidine. Effective sedative and analgesic duration seemed to be a function of when the largest dose was administered. Adequate additional sedative and analgesic could be gained from injections at doses of half of the initial one. The potent sedative and analgesic effects of medetomidine confirmed by neurologic evaluation supports its potential use as a premedication to general anesthesia in dogs. In this study, 2 different doses of medetomidine were also tested as premedication to both ketamine HCI and halothane anesthesia. Neorologic responses were determined at the same time cardiopulmonary parameters, anesthetic quality, and dose requirements were recorded. Medetomidine was found to have favorable qualities in conjunction with these anesthetics. Cardiopulmonary parameters remained satisfactory in both groups as preanesthetic medication prior to halothane, but no additional benefits could be seen from doses of 40 micrograms/kg medetomidine compared to 20 micrograms/kg, except a significant 30% reduction in halothane requirement. The positive chronotropic and inotropic properties of ketamine restored the medetomidine-induced bradycardia and produced a short anesthetic period of 15 to 30 min depending on the dose of medetomidine. The quality of anesthesia was better when 40 micrograms/kg medetomidine was used, but recovery was quicker with 20 micrograms/kg medetomidine. Medetomidine significantly reduced cerebral activity as demonstrated by recordings of total amplitude and frequency evaluation of the EEG with compressed spectral analysis. This analytical method was effective in confirming clinical signs of sedation, analgesia, and anesthesia in canine subjects.

Analgesia↗
PubMed1979

Sedimentation velocity separation: a preparation method for cervical samples.

A preparation procedure, aiming at monolayer deposition of cervical exfoliative material on glass slides for high resolution prescreening has been developed. The main features of this procedure are centrifugal deposition after suspension and sedimentation of samples over isopycnic medium of 1.026 density. Fractioning of the separation column after centrifugation at 50 X g yields two preparations with leukocytes, bacteria and cellular debris predominantly located on the first slide and epithelial cells on the second one. The degree of spatial cellular isolation as well as the amount of diagnostically relevant cells per slide seem to fit the requirements of automated high resolution analysis.

Cell Separation↗
PubMed1979

Cytomorphologic results of preparation experiments for monolayer deposition of cervical material.

For automated prescreening methods by high resolution analysis serving as a detecting method in gynecologic mass screening programs a new monolayer deposition method of cervical material has been used. This method will be outlines briefly and the mode of evaluation as well as current cytomorphological findings will be presented. With regard to measurability of the slides prepared according to the new method a number of cytologic criteria were thought to be of particular importance. These criteria are delineated and compiled in a table. A form in which these criteria were listed was filled in by cytopathologists for each slide evaluated. When performing isolation and centrifugation procedures several new morphologic questions arose to the cytopathologist which can only partly be answered by now. If taking into account all criteria of evaluation it may be followed from the present experiences that slides of cervical material are much more suited for automated prescreening methods by high resolution analysis if prepared after isolation and centrifugation in macromolecular liquids than are conventional Papanicolaou smears or slides from suspensions with isolated cells that were not subjected to centrifugation procedures.

Cell Separation↗
PubMed1979

[Suicide attempts with drugs].

A sample of 352 subjects, who had made a suicide attempt by ingesting pills examined in the aspects of age and sex, number and origin of used tablets and combination of pill ingestion with alcohol or other methods. Younger people under 20, took nearly exclusively tablets, which they accidentally found at home. Elder patients over 50, used nearly exclusively prescribed drugs. The typical patients attitudes to this suicidal method gives us the right to speak about such suicide attempts as "attempts by tablets". The pharmacological substance is unimportant and plays a secondary role. The seriousness of suicide attempts depends on topical situation of person, biological and social factors; it does'nt dependent on number or pharmacological substance of tablets.

Adult↗
PubMed1978

[Primary sarcomas of the gastrointestinal tract (author's transl)].

From 1952 to 1976 2203 malignant tumours of the gastrointestinal tract were seen at the Surgical Clinic of the M.H.L., 18 of them were sarcomas. There was a predominance of carcinomas of the stomach (Sa: Ca = 1:229) and of the colon (1:162), whereas sarcomas of the small intestine were found in a relation of 1:0,9. X-ray diagnosis of the gastric sarcomas is difficult, only those with endogastric growth can be recognized by gastroscopy. The postoperative prognosis of gastric sarcomas is better than that of gastric carcinomas. Sarcomas of the small intestine have a high mortality rate because of a high rate of ileus and perforation. Sarcomas of the colon - normally localized in the caecum or rectum - have a better prognosis, seldom stenosis can be seen.

Adult↗
PubMed1976

On the specificity of bovine spleen cathepsin B2.

The specificity of bovine spleen cathepsin B2 has been investigated by means of some natural oligo- and polypeptides, i.e. glucagon, melittin, insulin A and B chain, bradykinin, angiotensin I and II, oxytocin ACTH, clupein and salmin. The enzyme is primarily a carboxypeptidase which hydrolyzes peptide linkages of most amino acids common to proteins. In addition, cathepsin B2 displays amidase and esterase activity without requiring a free carboxyl group. The main pH optimum is between 4 and 5, in some cases higher.

Animals↗
PubMed1975

Improved purification of cathepsin B1 and cathepsin B2.

An improved purification of the cathepsins B1 and B2 from bovine spleen is described. In addition to the formerly used procedure, chromatography with DEAE-Sephadex or -cellulose and mercurated agarose is used. Both enzymes are obtained in an electrophoretically pure form but consist of two or more isoenzymes. The isolation procedure leads to enzymes with high specific activities in satisfactory yields. Cathepsin B1 is frequently accompanied by small amounts of an arylamidase-like enzyme that hydrolyzes leucine p-nitroanilide. However, very probably, cathepsin B1 itself has a low activity toward this substrate too. Cathepsin B2 has a comparatively high activity with its characteristic though not specific substrate, alpha-N-benzoyl-L-arginineamide, whereas the activity toward haemoglobin is far lower. Both enzymes possess an essential SH group and require EDTA and a mercaptane for full activity, but their stability is markedly impaired by storage at higher thiol concentrations; Some other properties of the enzymes are also discussed.

Animals↗
PubMedDate not supplied

Electroencephalographic power spectrum analysis as a monitor of anesthetic depth in horses.

Electroencephalographic (EEG) power spectrum analysis was performed in 18 conscious, adult horses for evaluation as control values for EEG data obtained during anesthesia. Computer-processed total amplitudes for the frequency range 0 to 32 Hz were mainly between 400 and 600 microV, with 80% spectral edge frequency between 16.6 and 32.5 Hz. The highest electrical activity was in the delta band (41.3 +/- 4.4% of total amplitude); there was a less pronounced activity in the beta (34.2 +/- 5.2%), theta (13.6 +/- 1.5%), and alpha (10.0 +/- 1.0%) bands. The applicability of EEG power spectrum analysis as a guide to depth of anesthesia was evaluated in four horses by comparing simultaneously recorded EEG data and clinical signs of anesthesia. Global changes in cerebrocortical electrical activity were detected with a single, monopolar (left frontoatlanto-occipital) EEG lead. Increasing depth of halothane anesthesia was accompanied by a pronounced shift in EEG activity from beta to theta and delta frequency bands, a decrease in 80% spectral edge frequency from 21.5 +/- 2.4 Hz to 12.6 +/- 2.2 Hz, a reduction in the beta/delta ratio of fractional amplitudes from 2.37 +/- 0.84 to 0.49 +/- 0.04, and a slight inconsistent increase in total amplitude from 96.1 +/- 37.3 microV to 185.5 +/- 53 microV. These results show that changes in the clinical signs of anesthetic depth in horses can be described numerically by use of EEG power spectrum analysis.

Anesthesia, General↗
PubMedDate not supplied

Components and results of a new preparation technique for automated analysis of cervical samples.

Components and evaluations of a new preparative procedure for automated high-resolution analysis of cervical samples are presented. This procedure is based on sedimentation velocity separation of samples with subsequent fractionation of the separation column and centrifugal deposition of suspended cells on coated glass slides. A system for specimen collection and mailing of suspended samples is described. A new type of glass slide designed for automated analysis is presented, and centrifugal buckets for cell deposition on a 6-sq-cm area are described. Experimental results with different kinds of coating substances for glass slides as well as different isopyknic media are discussed, and data for differential cell counts are graphically demonstrated. Looking at the diagnostic accuracy and economic feasibility of this system, the authors realize that preparations have to be evaluated quantitatively and that constraints of sample size and processing time have to be taken into consideration for further developments.

Autoanalysis↗
PubMedDate not supplied

Comparison of two Papanicolaou staining procedures for automated prescreening.

A "regressive" (procedure I) and a "progressive" (procedure II) modification of the Papanicolaou stain were tested for their suitability for automated screening procedures. Intermediate squamous cells and carcinoma cells were scanned with a high-resolution system, and digitized data were statistically analyzed after feature extraction. The regressive modification accentuates the textural features of intermediate squamous cell nuclei as well as the contrast ratio of nucleus and cytoplasm. The progressive modification accentuates some criteria of malignancy, such as polychromasia, hyperchromasia and shifting of nuclear to cytoplasmic ratio. Grouping of data according to patients indicates that the differences found are due to the staining procedures and not to individual variability of parameters in different patients.

Autoanalysis↗